Battery Terminal Replacement: Hydraulic Crimp - Die Size

Solder vs crimp debates pop up on most forums at some point or the other, with strong opinions on each side.

I'd much rather have a mechanical connection with a crimp on high amperage Lugs.

One reason, is that Tin solder is not super conductive.

On a conductivity scale of 1 to 100, 100 being pure copper,

Tin solder scores a 11.9.
Silver solder scores a 16.6

While either crimping or soldering can be done poorly, even a poorly done overcrimp is not going to fail mechanically, but a poorly soldered lug can have the cable pull from the lug. If it is a + cable and touches ground, the insulation will start smoking in under 2 seconds.

The hydraulic crimpers are a great tool to have for occassional use, but the metric dies sizes and different thickness lugs and cables, means one has to take more time to insure a proper crimp, perhaps rotating the crimp in the die and switching dies, stepping down in size.

When one is doing lots of crimps, then the cheap Hydraulic crimper becomes a time consuming liability.


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New Jersey
I prefer to crimp AND solder whenever I can.

Id agree fundamentally.

Challenge is getting the solder in. I’ve seen where a hole was drilled to get it from the end of the lug. Seemed to work well. For my use of this truck, I’m not going to take the risk of messing it up.
While I've not done it, I've a belt suspenders and a second belt acquaintance, who puts a small amount of solder in a lug, about 1/5th the amount one would use if soldering only, then heats it, then crimps it.

I use DeOxit Shield on new copper stranding before hydraulic crimping.

Smaller open end ring terminals, I remove the insulation, then crimp, then solder over the open stranding, then heatshrink.

My HF crimper came with ridiculously small dies. it does the red blue and yellow size connectors with insulation removed, very nicely, much much nicer than a dimple crimp or a buttcheek crimp, and certainly a clamshell crimp over the insulation.

Time consuming though.

often quick and dirty is more than good enough. with 10 AWG and smaller crimps.
I've done some connections like that, intending them to be temporary and then forget about them. Few have failed.

Beware of aluminum conductors in cheapo terminals/ crimps.

This is a good write up of just how far Ideal can be taken:

He shares his opinions on the crimp vs solder and the crimp then solder at the end.

I trust his logic and experience, and still will crimp then solder, but make sure solder hits nowhere that needs to remain flexible
Good article! On my own I drilled a hole in the nose (if I cant get the ones with a slit) and use liquid rosin flux and rosin solder in tin plated terminals. I never see any green snot on the cable itself after years.